![]() Metasequoia occidentalis appeared in fossil record during the Late Cretaceous epoch ( Cenomanian stage). The pollen-bearing cones are small, globose to ovoid, 1–5 mm (0.039–0.197 in) long and 0.5–4 mm (0.020–0.157 in) wide, and oppositely arranged on specialized stalks with one terminal cone. The seeds have two wings, are ovoid to cordate in shape, and are up to 5 mm (0.20 in) long and 4 mm (0.16 in) wide. The seed-bearing cones are globose to ovoid, 11–40 mm (0.43–1.57 in) long and 6–34 mm (0.24–1.34 in) wide, with decussately arranged triangular scales, and are borne on long, leafless stalks. The leaves are ovate to linear in shape, ranging from 6–25 mm (0.24–0.98 in) in length and 1–2 mm (0.039–0.079 in) in width, with a distinct midvein, a petiolate base, and an acute tip. The foliage consists of branchlets with oppositely arranged leaves. occidentalis was identical to a live Metasequoia glyptostroboides. With a few notable exceptions, it has been claimed that the majority of the fossils documented in the literature show that M. ![]() occidentalis by Ralph Works Chaney based on the close resemblance to living Metasequoia. In 1951, the species was reassigned to Metasequoia as M. It was not until the living species Metasequoia glyptostroboides was discovered and described from a remote area of China during the 1940s, that the affinity of many of the fossils became apparent. Fossilized Metasequoia-like remains were noted in Europe and North America from the 1800s on, but were assigned to the cupressaceous genera Sequoia (redwoods) and Taxodium ( bald cypresses). The species was originally described as Taxodium occidentale by John Strong Newberry. The species was first described in 1863 from fossils found in the outcrops of the Late Paleocene-Middle Eocene Chuckanut Formation around Birch Bay, Washington. occidentalis cone with long, leafless stalk Ypresian, Klondike Mountain Formation History
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